Water Purity and Needs
While everyone is used to using pure, clear drinking water from the tap to do everything from laundry to washing the car, there may be some things that don�t require water that is perfectly clean. To remain healthy, of course people need to drink pure water, but there are many jobs that aren�t as affected by water contaminants. Things like watering plants or the lawn don�t need chlorinated, fluoride-enriched drinking water to thrive and grow, and there are other jobs and duties as well that don�t need that pure, clean water to be performed.
Greywater
Greywater (sometimes spelled graywater, gray water, or grey water), is water that is left over from domestic use only, such as washing dishes, doing laundry, or taking showers. It is not left over water from industrial purposes. Greywater accounts for 50% to 80% of residential wastewater and is so named because of the gray color. Industries have been examining the uses for greywater in their manufacturing, though there are some drawbacks to this idea.
The recycling of greywater is generally seen as a good idea in theory, but when written out on paper, it might be too much trouble. Most places have laws against reusing untreated greywater because there are contaminants that might be harmful if ingested. But the price of treating greywater is often more than manufacturers want to pay for the recycling privileges, and it is more economic financially to just use clean water.
There are uses for greywater though, whether they are legal or not. Many rural areas are set up so that greywater is reused for the irrigation of fields. This can enrich the topsoil with nutrients from food waste, and encourage growth in plants, but is dangerous because it can make the plants toxic from bacteria in the water if not treated. With minor treatment, greywater can also be reused from bath and shower water in toilets, saving gallons of water a day. Yet, if left untreated too long, this too can cause health problems.
Industries have also talked of using greywater in places that are being developed under extreme living conditions. It is easier to develop a place like that if a water treatment system doesn�t have to be put in immediately. Of course, this can lead to illness from bacteria. There is another idea as well that uses the residual heat from greywater to head clean water that is coming in. This can save on home heating bills immensely.
Blackwater
The other type of waste water, or used water, is called blackwater. Blackwater is water that has been contaminated with human bodily waste, or toxic chemicals from companies. The term blackwater comes from the color of the water. It is most commonly known as sewage, and for that reason, is generally not used for anything. Blackwater is very difficult to treat because of all the bacteria and harmful contaminants in it, and it isn�t recommended for any kind of reuse.
Utilizing Used Water
Used water can be utilized in several ways before it is sent away from the home completely. Watering plants is the most prominent of the ideas, mostly because it adds nutrients to the soil. But greywater that is reused for that purpose should be used immediately and never stored away, as that gives it time to grow more bacteria.
Another concept would be to use wash water again on something like the dishes first, then the car. The harmful chemicals that are already in the water came from soaps and organic material, and adding more soap won�t harm your car as long as you rinse it off in clean water. But there is always the risk of unintentional inhalation of the dirty water.
Whether a company treats water or not after it has been used is still up in the air for many places. There is some use for used water, though mostly greywater is what can be reused. Blackwater is too harmful to be practically recycled at the home, but steps are being taken all the time to ensure that some day there will be more water recycling.